1. Technical Field of the Invention
The present invention relates to a mobile telecommunications network and, in particular, to the provision of multiple home zones and variable charging rates toward associated mobile subscribers.
2. Description of Related Art
With the introduction of the Global Standard for Mobile (GSM) communication and the Personal Communications System (PCS), the concepts of wireline telephone service and wireless telephone service have changed drastically. Instead of assigning a telephone number for a particular geographic location or a particular telecommunications terminal, in accordance with the GSM or PCS, a telephone number may be instead assigned towards a particular subscriber or subscription. As a result, each subscriber is associated with a Subscriber Identity Module (SIM) card. Using the SIM card, a mobile subscriber is able to store necessary mobile subscriber information in a detachable memory unit and freely associate the card with any available mobile station (also referred to as a mobile terminal, and mobile equipment, and hereinafter collectively referred to as a "mobile station") By inserting a mobile subscriber's SIM card into a mobile station, the stored subscriber information in the inserted SIM card is available to the mobile subscriber's new terminal. As a result, the mobile subscriber is able to freely utilize any available mobile station while maintaining the same directory number and subscriber feature data.
Furthermore, in order to enable the mobile subscriber to utilize the mobile station in a manner similar to a cordless phone for charging purposes, the concept of a "home zone" has been introduced. If the mobile subscriber makes a call within his home zone, the mobile subscriber is not charged for the air time, or is charged at a significantly lower air time rate. Accordingly, within the home zone, such as the subscriber's home or office, the mobile subscriber can still utilize the associated mobile station to originate outgoing calls and to receive incoming calls without incurring expensive air time charges and without physically using a different telephone terminal, e.g., wireline terminal.
With a conventional cordless terminal, the radio frequency communications range with the serving base unit is rather limited. Consequently, a subscriber is not able to travel out of the immediate vicinity of the base unit and utilize the cordless terminal. However, with a PCS or GSM based telecommunications network, home zone service is still provided by the same mobile switching center (MSC) serving that particular geographic location. Therefore, with the conventional cordless system, it was a physical limitation that imposed the geographic boundaries of the service area. In contrast, within the GSM or PCS network, it is a logical limitation that imposes the geographic boundaries of the mobile subscriber's home zone. Accordingly, the home zone associated with a particular mobile subscriber can be much larger than what was previously available with the conventional cordless system. This logical limitation may include only a few blocks from his home, or a radius of half kilometer, for example, covering a certain location. Once the mobile subscriber travels outside of the associated home zone, regular air time billing resumes.
For a typical mobile subscriber, it would be desirable to be able to associate or designate a number of different home zones and select one of those home zones as being in effect at a given time as the mobile subscriber moves from one geographic location to another geographic location. As an example, during business hours, a first geographic area, such as the place of work, would be designated as the home zone. On the other hand, after work, a second geographic area, such as home, would be designated as the home zone. Such variations in the size and location of the home zone may further differ for different times of the day or days of the week.
With a conventional wireless system, however, only one home zone can be assigned and associated with a mobile subscriber or subscription. Accordingly, if the mobile subscriber needs to change his home zone designation, he needs to inconveniently notify the service operator and designate a new area as his home zone. If the subscriber changes from one geographic area to another geographic area with a regular schedule, such changes further have to be made repeatedly in accordance with his schedule.
Accordingly, there is a need for a mechanism to enable a serving mobile telecommunications network to provide variable home zones for a particular mobile subscriber.